add basic email functionality, not hooked up to anything
Merge branch 'master' into email
add flask-mail to requirements
Merge branch 'master' into email

Conflicts:
	cbbpoll/__init__.py
Merge branch 'master' into email
Merge branch 'master' into email
Add email reminders for poll open and close

Reminders are sent three days and 12 hours prior to poll closing.
Reminders should be setup as hourly cron job, by running "manger.py remind viaEmail"
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